EXIF Distance information on EOS lenses

[df-gallery]

I was recently looking at the EXIF data through Capture One and

noticed that my 70-200/4 did show focus distance information, whereas

my 50/2.5 macro didn't? Is there a reason why only certain lenses will

show focus distance information? Would it be correct to assume that

USM lenses will provide focus distance information, whereas AFD lenses

won't? Or is it a little more complex than that? Thanks, David.

[picturesque]

Look at the following list of lenses that provide distance data and lenses that don't. Your 50mm isn't on the list that does, and there are USM lenses that don't, like the 50mm f1.4 USM.

 

http://photonotes.org/articles/eos-flash/#distancedata

[kbroderick]

<p>There's a pretty good list at <a href="http://photonotes.org/articles/eos-flash/

#distancedata">the EOS Flash FAQ</a>; it's there in part because the E-TTL II system can

use focal-distance-data on some cameras when calculating flash intensity; USM is

sometimes--but not always--a hint. The list is not claimed to be definitive, though.</p>

[roisin_murphy]

can you see that distance info in irfanview or some other exif viewer? my 200mm prime should also report it, but i cant find it in the exif...

[steve_dunn2]

<p>My 20D does not report subject distance in the EXIF tags, even though 2 or 3 (depending on what source you read; I believe 3) of my 4 lenses do report it to the camera. DPP, EVU, and ACR do not provide this information, either, so I think it's safe to say that the 20D simply does not record it in any of the files it creates. Some older EOS DSLRs apparently do, which is a bit silly since older EOS DSLRs don't actually use the focus distance info whereas the 20D does.</p>

 

<p>As a general guideline, ring USM lenses with mechanical full-time manual focusing provide it; others (ring USM lenses with electronic FT-M, micro USM, and non-USM) do not. But that's a guideline, not a hard-and-fast rule.</p>

[steve_dunn2]

<p>Just to clarify, when I posted that DPP, EVU, and ACR can't find the subject distance, I'm using them to try to get it from the CR2 (RAW) files. For JPEGs, I'm using Irfanview and IExif.</p>

[awindsor]

The subject distance isn't provided or isn;t accessible in the EXIF metadata, for the following camera bodies:

 

Canon 350D, Canon 20D, Canon 1Ds, Canon 1Ds Mark II, Canon 1D Mark II, Konica Minolta 7D, Konica Minolta A2, Sony DSC-F828.

 

I don't know about the new Canon 5D.

 

The distance is not very precise and I guess Canon didn't want it being "misused".

 

David doesn't mention what body he is using but my guess would be a 300D/Digital Rebel.